1. Field of the Invention
The present invention relates to molecular gas storage, and more particularly to a method and apparatus for containing a molecular gas by sorption in storage sites of a nano-filament laded reticulated structure.
2. Related Art
Hydrogen has become progressively more attractive as an energy source as the price of petroleum increases and its availability declines. Hydrogen is particularly interesting as a fuel because it has the highest energy density per unit weight of any chemical fuel, and because hydrogen can be used directly in a variety of energy converters from reciprocating internal combustion engines to hydrogen fuel cells.
In the art of hydrogen fuel cells, there is an ongoing search for new and improved hydrogen power-generating cells and hydrogen storage systems. Power-generating cells may eventually replace other power generating systems, such as internal combustion engines. Improvements in hydrogen storage systems will make it possible to store enough hydrogen in small storage configurations to not only provide fuel to vehicles, but to one day provide power to cell phones, computers, camcorders and other cordless devices.
Unfortunately, hydrogen is a highly volatile fuel, and its storage in satisfactory quantities to be a commercially viable fuel has been a major obstacle to implementation of hydrogen-based energy systems.
Several methods of storing hydrogen currently exist, but are either inadequate or impractical for most consumer applications. For example, hydrogen can be stored in liquid form at very low temperatures. Cryogenic storage, however, only provides a volume density of 70 grams of hydrogen per liter, which is clearly insufficient for most consumer applications. In addition, the energy consumed in liquefying hydrogen gas is about 60% of the energy available from the resulting hydrogen.
Some hydrogen is stored under high pressure in cylinders. However, a 100-pound steel cylinder can only store about one pound of hydrogen at about 2200 psi, which translates into 1% by weight of hydrogen storage. More expensive composite cylinders with special compressors can store hydrogen at higher pressures of about 4,500 psi to achieve a more favorable storage ratio of about 4% by weight. Although even higher pressures are possible, safety factors and the high amount of energy consumed in achieving such high pressures have compelled a search for alternative hydrogen storage technologies that are both safe and efficient.
In view of the above, there is a need for safer, more effective methods of storing and recovering hydrogen.